Same filename and directory in other branches
  1. 8.9.x core/modules/comment/comment.module
  2. 9 core/modules/comment/comment.module

Enables users to comment on published content.

When installed, the Comment module creates a field that facilitates a discussion board for each Drupal entity to which a comment field is attached. Users can post comments to discuss a story, user etc.

File

core/modules/comment/comment.module
View source
<?php

/**
 * @file
 * Enables users to comment on published content.
 *
 * When installed, the Comment module creates a field that facilitates a
 * discussion board for each Drupal entity to which a comment field is attached.
 * Users can post comments to discuss a story, user etc.
 */
use Drupal\comment\CommentInterface;
use Drupal\comment\Entity\CommentType;
use Drupal\Core\Entity\FieldableEntityInterface;
use Drupal\comment\Plugin\Field\FieldType\CommentItemInterface;
use Drupal\Core\Entity\Entity\EntityViewMode;
use Drupal\Core\Entity\EntityInterface;
use Drupal\Core\Field\FieldTypeCategoryManagerInterface;
use Drupal\Core\Form\FormStateInterface;
use Drupal\Core\Routing\RouteMatchInterface;
use Drupal\Core\Entity\Display\EntityViewDisplayInterface;
use Drupal\Core\Render\Element;
use Drupal\Core\Link;
use Drupal\Core\Url;
use Drupal\field\FieldConfigInterface;
use Drupal\field\FieldStorageConfigInterface;
use Drupal\node\NodeInterface;
use Drupal\user\RoleInterface;
use Drupal\user\UserInterface;

/**
 * The time cutoff for comments marked as read for entity types other node.
 *
 * Comments changed before this time are always marked as read.
 * Comments changed after this time may be marked new, updated, or read,
 * depending on their state for the current user. Defaults to 30 days ago.
 *
 * @todo Remove when https://www.drupal.org/node/2006632 lands.
 */
define('COMMENT_NEW_LIMIT', (int) $_SERVER['REQUEST_TIME'] - 30 * 24 * 60 * 60);

/**
 * Implements hook_help().
 */
function comment_help($route_name, RouteMatchInterface $route_match) {
  switch ($route_name) {
    case 'help.page.comment':
      $output = '<h2>' . t('About') . '</h2>';
      $output .= '<p>' . t('The Comment module allows users to comment on site content, set commenting defaults and permissions, and moderate comments. For more information, see the <a href=":comment">online documentation for the Comment module</a>.', [
        ':comment' => 'https://www.drupal.org/documentation/modules/comment',
      ]) . '</p>';
      $output .= '<h2>' . t('Uses') . '</h2>';
      $output .= '<dl>';
      $output .= '<dt>' . t('Enabling commenting') . '</dt>';
      $output .= '<dd>' . t('Comment functionality can be enabled for any entity sub-type (for example, a <a href=":content-type">content type</a>) by adding a <em>Comments</em> field on its <em>Manage fields page</em>. Adding or removing commenting for an entity through the user interface requires the <a href=":field_ui">Field UI</a> module to be installed, even though the commenting functionality works without it. For more information on fields and entities, see the <a href=":field">Field module help page</a>.', [
        ':content-type' => \Drupal::moduleHandler()
          ->moduleExists('node') ? Url::fromRoute('entity.node_type.collection')
          ->toString() : '#',
        ':field' => Url::fromRoute('help.page', [
          'name' => 'field',
        ])
          ->toString(),
        ':field_ui' => \Drupal::moduleHandler()
          ->moduleExists('field_ui') ? Url::fromRoute('help.page', [
          'name' => 'field_ui',
        ])
          ->toString() : '#',
      ]) . '</dd>';
      $output .= '<dt>' . t('Configuring commenting settings') . '</dt>';
      $output .= '<dd>' . t('Commenting settings can be configured by editing the <em>Comments</em> field on the <em>Manage fields page</em> of an entity type if the <em>Field UI module</em> is installed. Configuration includes the label of the comments field, the number of comments to be displayed, and whether they are shown in threaded list. Commenting can be configured as: <em>Open</em> to allow new comments, <em>Closed</em> to view existing comments, but prevent new comments, or <em>Hidden</em> to hide existing comments and prevent new comments. Changing this configuration for an entity type will not change existing entity items.') . '</dd>';
      $output .= '<dt>' . t('Overriding default settings') . '</dt>';
      $output .= '<dd>' . t('Users with the appropriate permissions can override the default commenting settings of an entity type when they create an item of that type.') . '</dd>';
      $output .= '<dt>' . t('Adding comment types') . '</dt>';
      $output .= '<dd>' . t('Additional <em>comment types</em> can be created per entity sub-type and added on the <a href=":field">Comment types page</a>. If there are multiple comment types available you can select the appropriate one after adding a <em>Comments field</em>.', [
        ':field' => Url::fromRoute('entity.comment_type.collection')
          ->toString(),
      ]) . '</dd>';
      $output .= '<dt>' . t('Approving and managing comments') . '</dt>';
      $output .= '<dd>' . t('Comments from users who have the <em>Skip comment approval</em> permission are published immediately. All other comments are placed in the <a href=":comment-approval">Unapproved comments</a> queue, until a user who has permission to <em>Administer comments and comment settings</em> publishes or deletes them. Published comments can be bulk managed on the <a href=":admin-comment">Published comments</a> administration page. When a comment has no replies, it remains editable by its author, as long as the author has <em>Edit own comments</em> permission.', [
        ':comment-approval' => Url::fromRoute('comment.admin_approval')
          ->toString(),
        ':admin-comment' => Url::fromRoute('comment.admin')
          ->toString(),
      ]) . '</dd>';
      $output .= '</dl>';
      return $output;
    case 'entity.comment_type.collection':
      $output = '<p>' . t('This page provides a list of all comment types on the site and allows you to manage the fields, form and display settings for each.') . '</p>';
      return $output;
  }
}

/**
 * Entity URI callback.
 */
function comment_uri(CommentInterface $comment) {
  return new Url('entity.comment.canonical', [
    'comment' => $comment
      ->id(),
  ], [
    'fragment' => 'comment-' . $comment
      ->id(),
  ]);
}

/**
 * Implements hook_entity_extra_field_info().
 */
function comment_entity_extra_field_info() {
  $return = [];
  foreach (CommentType::loadMultiple() as $comment_type) {
    $return['comment'][$comment_type
      ->id()] = [
      'form' => [
        'author' => [
          'label' => t('Author'),
          'description' => t('Author textfield'),
          'weight' => -2,
        ],
      ],
    ];
    $return['comment'][$comment_type
      ->id()]['display']['links'] = [
      'label' => t('Links'),
      'description' => t('Comment operation links'),
      'weight' => 100,
      'visible' => TRUE,
    ];
  }
  return $return;
}

/**
 * Implements hook_theme().
 */
function comment_theme() {
  return [
    'comment' => [
      'render element' => 'elements',
    ],
    'field__comment' => [
      'base hook' => 'field',
    ],
  ];
}

/**
 * Implements hook_ENTITY_TYPE_create() for 'field_config'.
 */
function comment_field_config_create(FieldConfigInterface $field) {
  if ($field
    ->getType() == 'comment' && !$field
    ->isSyncing()) {

    // Assign default values for the field.
    $default_value = $field
      ->getDefaultValueLiteral();
    $default_value += [
      [],
    ];
    $default_value[0] += [
      'status' => CommentItemInterface::OPEN,
      'cid' => 0,
      'last_comment_timestamp' => 0,
      'last_comment_name' => '',
      'last_comment_uid' => 0,
      'comment_count' => 0,
    ];
    $field
      ->setDefaultValue($default_value);
  }
}

/**
 * Implements hook_ENTITY_TYPE_update() for 'field_config'.
 */
function comment_field_config_update(FieldConfigInterface $field) {
  if ($field
    ->getType() == 'comment') {

    // Comment field settings also affects the rendering of *comment* entities,
    // not only the *commented* entities.
    \Drupal::entityTypeManager()
      ->getViewBuilder('comment')
      ->resetCache();
  }
}

/**
 * Implements hook_ENTITY_TYPE_insert() for 'field_storage_config'.
 */
function comment_field_storage_config_insert(FieldStorageConfigInterface $field_storage) {
  if ($field_storage
    ->getType() == 'comment') {

    // Check that the target entity type uses an integer ID.
    $entity_type_id = $field_storage
      ->getTargetEntityTypeId();
    if (!_comment_entity_uses_integer_id($entity_type_id)) {
      throw new \UnexpectedValueException('You cannot attach a comment field to an entity with a non-integer ID field');
    }
  }
}

/**
 * Implements hook_ENTITY_TYPE_delete() for 'field_config'.
 */
function comment_field_config_delete(FieldConfigInterface $field) {
  if ($field
    ->getType() == 'comment') {

    // Delete all comments that used by the entity bundle.
    $entity_query = \Drupal::entityQuery('comment')
      ->accessCheck(FALSE);
    $entity_query
      ->condition('entity_type', $field
      ->getEntityTypeId());
    $entity_query
      ->condition('field_name', $field
      ->getName());
    $cids = $entity_query
      ->execute();
    $comment_storage = \Drupal::entityTypeManager()
      ->getStorage('comment');
    $comments = $comment_storage
      ->loadMultiple($cids);
    $comment_storage
      ->delete($comments);
  }
}

/**
 * Implements hook_node_links_alter().
 */
function comment_node_links_alter(array &$links, NodeInterface $node, array &$context) {

  // Comment links are only added to node entity type for backwards
  // compatibility. Should you require comment links for other entity types you
  // can do so by implementing a new field formatter.
  // @todo Make this configurable from the formatter. See
  //   https://www.drupal.org/node/1901110.
  $comment_links = \Drupal::service('comment.link_builder')
    ->buildCommentedEntityLinks($node, $context);
  $links += $comment_links;
}

/**
 * Implements hook_entity_view().
 */
function comment_entity_view(array &$build, EntityInterface $entity, EntityViewDisplayInterface $display, $view_mode) {
  if ($entity instanceof FieldableEntityInterface && $view_mode == 'rss' && $display
    ->getComponent('links')) {

    /** @var \Drupal\comment\CommentManagerInterface $comment_manager */
    $comment_manager = \Drupal::service('comment.manager');
    $fields = $comment_manager
      ->getFields($entity
      ->getEntityTypeId());
    foreach ($fields as $field_name => $detail) {
      if ($entity
        ->hasField($field_name) && $entity
        ->get($field_name)->status != CommentItemInterface::HIDDEN) {

        // Add a comments RSS element which is a URL to the comments of this
        // entity.
        $options = [
          'fragment' => 'comments',
          'absolute' => TRUE,
        ];
        $entity->rss_elements[] = [
          'key' => 'comments',
          'value' => $entity
            ->toUrl('canonical', $options)
            ->toString(),
        ];
      }
    }
  }
}

/**
 * Implements hook_ENTITY_TYPE_view_alter() for node entities.
 */
function comment_node_view_alter(array &$build, EntityInterface $node, EntityViewDisplayInterface $display) {
  if (\Drupal::moduleHandler()
    ->moduleExists('history')) {
    $build['#attributes']['data-history-node-id'] = $node
      ->id();
  }
}

/**
 * Implements hook_form_FORM_ID_alter() for field_ui_field_storage_add_form.
 */
function comment_form_field_ui_field_storage_add_form_alter(&$form, FormStateInterface $form_state) {
  $route_match = \Drupal::routeMatch();
  if ($form_state
    ->get('entity_type_id') == 'comment' && $route_match
    ->getParameter('commented_entity_type')) {
    $form['#title'] = \Drupal::service('comment.manager')
      ->getFieldUIPageTitle($route_match
      ->getParameter('commented_entity_type'), $route_match
      ->getParameter('field_name'));
  }
}

/**
 * Implements hook_field_info_entity_type_ui_definitions_alter().
 */
function comment_field_info_entity_type_ui_definitions_alter(array &$ui_definitions, string $entity_type_id) {
  if (!_comment_entity_uses_integer_id($entity_type_id)) {
    unset($ui_definitions['comment']);
  }
}

/**
 * Implements hook_form_FORM_ID_alter().
 */
function comment_form_field_ui_form_display_overview_form_alter(&$form, FormStateInterface $form_state) {
  $route_match = \Drupal::routeMatch();
  if ($form['#entity_type'] == 'comment' && $route_match
    ->getParameter('commented_entity_type')) {
    $form['#title'] = \Drupal::service('comment.manager')
      ->getFieldUIPageTitle($route_match
      ->getParameter('commented_entity_type'), $route_match
      ->getParameter('field_name'));
  }
}

/**
 * Implements hook_form_FORM_ID_alter().
 */
function comment_form_field_ui_display_overview_form_alter(&$form, FormStateInterface $form_state) {
  $route_match = \Drupal::routeMatch();
  if ($form['#entity_type'] == 'comment' && $route_match
    ->getParameter('commented_entity_type')) {
    $form['#title'] = \Drupal::service('comment.manager')
      ->getFieldUIPageTitle($route_match
      ->getParameter('commented_entity_type'), $route_match
      ->getParameter('field_name'));
  }
}

/**
 * Implements hook_entity_storage_load().
 *
 * @see \Drupal\comment\Plugin\Field\FieldType\CommentItem::propertyDefinitions()
 */
function comment_entity_storage_load($entities, $entity_type) {

  // Comments can only be attached to content entities, so skip others.
  if (!\Drupal::entityTypeManager()
    ->getDefinition($entity_type)
    ->entityClassImplements(FieldableEntityInterface::class)) {
    return;
  }
  if (!\Drupal::service('comment.manager')
    ->getFields($entity_type)) {

    // Do not query database when entity has no comment fields.
    return;
  }

  // Load comment information from the database and update the entity's
  // comment statistics properties, which are defined on each CommentItem field.
  $result = \Drupal::service('comment.statistics')
    ->read($entities, $entity_type);
  foreach ($result as $record) {

    // Skip fields that entity does not have.
    if (!$entities[$record->entity_id]
      ->hasField($record->field_name)) {
      continue;
    }
    $comment_statistics = $entities[$record->entity_id]
      ->get($record->field_name);
    $comment_statistics->cid = $record->cid;
    $comment_statistics->last_comment_timestamp = $record->last_comment_timestamp;
    $comment_statistics->last_comment_name = $record->last_comment_name;
    $comment_statistics->last_comment_uid = $record->last_comment_uid;
    $comment_statistics->comment_count = $record->comment_count;
  }
}

/**
 * Implements hook_entity_insert().
 */
function comment_entity_insert(EntityInterface $entity) {

  // Allow bulk updates and inserts to temporarily disable the
  // maintenance of the {comment_entity_statistics} table.
  if (\Drupal::state()
    ->get('comment.maintain_entity_statistics') && ($fields = \Drupal::service('comment.manager')
    ->getFields($entity
    ->getEntityTypeId()))) {
    \Drupal::service('comment.statistics')
      ->create($entity, $fields);
  }
}

/**
 * Implements hook_entity_predelete().
 */
function comment_entity_predelete(EntityInterface $entity) {

  // Entities can have non-numeric IDs, but {comment} and
  // {comment_entity_statistics} tables have integer columns for entity ID, and
  // PostgreSQL throws exceptions if you attempt query conditions with
  // mismatched types. So, we need to verify that the ID is numeric (even for an
  // entity type that has an integer ID, $entity->id() might be a string
  // containing a number), and then cast it to an integer when querying.
  if ($entity instanceof FieldableEntityInterface && is_numeric($entity
    ->id())) {
    $entity_query = \Drupal::entityQuery('comment')
      ->accessCheck(FALSE);
    $entity_query
      ->condition('entity_id', (int) $entity
      ->id());
    $entity_query
      ->condition('entity_type', $entity
      ->getEntityTypeId());
    $cids = $entity_query
      ->execute();
    $comment_storage = \Drupal::entityTypeManager()
      ->getStorage('comment');
    $comments = $comment_storage
      ->loadMultiple($cids);
    $comment_storage
      ->delete($comments);
    \Drupal::service('comment.statistics')
      ->delete($entity);
  }
}

/**
 * Determines if an entity type is using an integer-based ID definition.
 *
 * @param string $entity_type_id
 *   The ID the represents the entity type.
 *
 * @return bool
 *   Returns TRUE if the entity type has an integer-based ID definition and
 *   FALSE otherwise.
 */
function _comment_entity_uses_integer_id($entity_type_id) {
  $entity_type = \Drupal::entityTypeManager()
    ->getDefinition($entity_type_id);
  $entity_type_id_key = $entity_type
    ->getKey('id');
  if ($entity_type_id_key === FALSE) {
    return FALSE;
  }
  $field_definitions = \Drupal::service('entity_field.manager')
    ->getBaseFieldDefinitions($entity_type
    ->id());
  $entity_type_id_definition = $field_definitions[$entity_type_id_key];
  return $entity_type_id_definition
    ->getType() === 'integer';
}

/**
 * Implements hook_node_update_index().
 */
function comment_node_update_index(EntityInterface $node) {
  $index_comments =& drupal_static(__FUNCTION__);
  if ($index_comments === NULL) {

    // Do not index in the following three cases:
    // 1. 'Authenticated user' can search content but can't access comments.
    // 2. 'Anonymous user' can search content but can't access comments.
    // 3. Any role can search content but can't access comments and access
    // comments is not granted by the 'authenticated user' role. In this case
    // all users might have both permissions from various roles but it is also
    // possible to set up a user to have only search content and so a user
    // edit could change the security situation so it is not safe to index the
    // comments.
    $index_comments = TRUE;
    $roles = \Drupal::entityTypeManager()
      ->getStorage('user_role')
      ->loadMultiple();
    $authenticated_can_access = $roles[RoleInterface::AUTHENTICATED_ID]
      ->hasPermission('access comments');
    foreach ($roles as $rid => $role) {
      if ($role
        ->hasPermission('search content') && !$role
        ->hasPermission('access comments')) {
        if ($rid == RoleInterface::AUTHENTICATED_ID || $rid == RoleInterface::ANONYMOUS_ID || !$authenticated_can_access) {
          $index_comments = FALSE;
          break;
        }
      }
    }
  }
  $build = [];
  if ($index_comments) {
    foreach (\Drupal::service('comment.manager')
      ->getFields('node') as $field_name => $info) {

      // Skip fields that entity does not have.
      if (!$node
        ->hasField($field_name)) {
        continue;
      }
      $field_definition = $node
        ->getFieldDefinition($field_name);
      $mode = $field_definition
        ->getSetting('default_mode');
      $comments_per_page = $field_definition
        ->getSetting('per_page');
      if ($node
        ->get($field_name)->status) {
        $comments = \Drupal::entityTypeManager()
          ->getStorage('comment')
          ->loadThread($node, $field_name, $mode, $comments_per_page);
        if ($comments) {
          $build[] = \Drupal::entityTypeManager()
            ->getViewBuilder('comment')
            ->viewMultiple($comments);
        }
      }
    }
  }
  return \Drupal::service('renderer')
    ->renderInIsolation($build);
}

/**
 * Implements hook_cron().
 */
function comment_cron() {

  // Store the maximum possible comments per thread (used for node search
  // ranking by reply count).
  \Drupal::state()
    ->set('comment.node_comment_statistics_scale', 1.0 / max(1, \Drupal::service('comment.statistics')
    ->getMaximumCount('node')));
}

/**
 * Implements hook_node_search_result().
 *
 * Formats a comment count string and returns it, for display with search
 * results.
 */
function comment_node_search_result(EntityInterface $node) {
  $comment_fields = \Drupal::service('comment.manager')
    ->getFields('node');
  $comments = 0;
  $open = FALSE;
  foreach ($comment_fields as $field_name => $info) {

    // Skip fields that entity does not have.
    if (!$node
      ->hasField($field_name)) {
      continue;
    }

    // Do not make a string if comments are hidden.
    $status = $node
      ->get($field_name)->status;
    if (\Drupal::currentUser()
      ->hasPermission('access comments') && $status != CommentItemInterface::HIDDEN) {
      if ($status == CommentItemInterface::OPEN) {

        // At least one comment field is open.
        $open = TRUE;
      }
      $comments += $node
        ->get($field_name)->comment_count;
    }
  }

  // Do not make a string if there are no comment fields, or no comments exist
  // or all comment fields are hidden.
  if ($comments > 0 || $open) {
    return [
      'comment' => \Drupal::translation()
        ->formatPlural($comments, '1 comment', '@count comments'),
    ];
  }
}

/**
 * Implements hook_user_cancel().
 */
function comment_user_cancel($edit, UserInterface $account, $method) {
  switch ($method) {
    case 'user_cancel_block_unpublish':
      $comments = \Drupal::entityTypeManager()
        ->getStorage('comment')
        ->loadByProperties([
        'uid' => $account
          ->id(),
      ]);
      foreach ($comments as $comment) {
        $comment
          ->setUnpublished();
        $comment
          ->save();
      }
      break;
    case 'user_cancel_reassign':

      /** @var \Drupal\comment\CommentInterface[] $comments */
      $comments = \Drupal::entityTypeManager()
        ->getStorage('comment')
        ->loadByProperties([
        'uid' => $account
          ->id(),
      ]);
      foreach ($comments as $comment) {
        $langcodes = array_keys($comment
          ->getTranslationLanguages());

        // For efficiency manually save the original comment before applying any
        // changes.
        $comment->original = clone $comment;
        foreach ($langcodes as $langcode) {
          $comment_translated = $comment
            ->getTranslation($langcode);
          $comment_translated
            ->setOwnerId(0);
          $comment_translated
            ->setAuthorName(\Drupal::config('user.settings')
            ->get('anonymous'));
        }
        $comment
          ->save();
      }
      break;
  }
}

/**
 * Implements hook_ENTITY_TYPE_predelete() for user entities.
 */
function comment_user_predelete($account) {
  $entity_query = \Drupal::entityQuery('comment')
    ->accessCheck(FALSE);
  $entity_query
    ->condition('uid', $account
    ->id());
  $cids = $entity_query
    ->execute();
  $comment_storage = \Drupal::entityTypeManager()
    ->getStorage('comment');
  $comments = $comment_storage
    ->loadMultiple($cids);
  $comment_storage
    ->delete($comments);
}

/**
 * Generates a comment preview.
 *
 * @param \Drupal\comment\CommentInterface $comment
 *   The comment entity to preview.
 * @param Drupal\Core\Form\FormStateInterface $form_state
 *   The current state of the form.
 *
 * @return array
 *   An array as expected by \Drupal\Core\Render\RendererInterface::render().
 */
function comment_preview(CommentInterface $comment, FormStateInterface $form_state) {
  $preview_build = [];
  $entity = $comment
    ->getCommentedEntity();
  if (!$form_state
    ->getErrors()) {
    $comment->in_preview = TRUE;
    $comment_build = \Drupal::entityTypeManager()
      ->getViewBuilder('comment')
      ->view($comment);
    $comment_build['#weight'] = -100;
    $preview_build['comment_preview'] = $comment_build;
  }
  if ($comment
    ->hasParentComment()) {
    $build = [];
    $parent = $comment
      ->getParentComment();
    if ($parent && $parent
      ->isPublished()) {
      $build = \Drupal::entityTypeManager()
        ->getViewBuilder('comment')
        ->view($parent);
    }
  }
  else {

    // The comment field output includes rendering the parent entity of the
    // thread to which the comment is a reply. The rendered entity output
    // includes the comment reply form, which contains the comment preview and
    // therefore the rendered parent entity. This results in an infinite loop of
    // parent entity output rendering the comment form and the comment form
    // rendering the parent entity. To prevent this infinite loop we temporarily
    // set the value of the comment field on a clone of the entity to hidden
    // before calling the entity view builder. That way when the output of
    // the commented entity is rendered, it excludes the comment field output.
    $field_name = $comment
      ->getFieldName();
    $entity = clone $entity;
    $entity->{$field_name}->status = CommentItemInterface::HIDDEN;
    $build = \Drupal::entityTypeManager()
      ->getViewBuilder($entity
      ->getEntityTypeId())
      ->view($entity, 'full');
  }
  $preview_build['comment_output_below'] = $build;
  $preview_build['comment_output_below']['#weight'] = 200;
  return $preview_build;
}

/**
 * Implements hook_preprocess_HOOK() for block templates.
 */
function comment_preprocess_block(&$variables) {
  if ($variables['configuration']['provider'] == 'comment') {
    $variables['attributes']['role'] = 'navigation';
  }
}

/**
 * Prepares variables for comment templates.
 *
 * By default this function performs special preprocessing of some base fields
 * so they are available as variables in the template. For example 'subject'
 * appears as 'title'. This preprocessing is skipped if:
 * - a module makes the field's display configurable via the field UI by means
 *   of BaseFieldDefinition::setDisplayConfigurable()
 * - AND the additional entity type property
 *   'enable_base_field_custom_preprocess_skipping' has been set using
 *   hook_entity_type_build().
 *
 * Default template: comment.html.twig.
 *
 * @param array $variables
 *   An associative array containing:
 *   - elements: An associative array containing the comment and entity objects.
 *     Array keys: #comment, #commented_entity.
 */
function template_preprocess_comment(&$variables) {

  /** @var \Drupal\Core\Datetime\DateFormatterInterface $date_formatter */
  $date_formatter = \Drupal::service('date.formatter');

  /** @var \Drupal\comment\CommentInterface $comment */
  $comment = $variables['elements']['#comment'];
  $commented_entity = $comment
    ->getCommentedEntity();
  $variables['comment'] = $comment;
  $variables['commented_entity'] = $commented_entity;
  $variables['threaded'] = $variables['elements']['#comment_threaded'];
  $skip_custom_preprocessing = $comment
    ->getEntityType()
    ->get('enable_base_field_custom_preprocess_skipping');

  // Make created, uid, pid and subject fields available separately. Skip this
  // custom preprocessing if the field display is configurable and skipping has
  // been enabled.
  // @todo https://www.drupal.org/project/drupal/issues/3015623
  //   Eventually delete this code and matching template lines. Using
  //   $variables['content'] is more flexible and consistent.
  $submitted_configurable = $comment
    ->getFieldDefinition('created')
    ->isDisplayConfigurable('view') || $comment
    ->getFieldDefinition('uid')
    ->isDisplayConfigurable('view');
  if (!$skip_custom_preprocessing || !$submitted_configurable) {
    $account = $comment
      ->getOwner();
    $username = [
      '#theme' => 'username',
      '#account' => $account,
    ];
    $variables['author'] = \Drupal::service('renderer')
      ->render($username);
    $variables['author_id'] = $comment
      ->getOwnerId();
    $variables['new_indicator_timestamp'] = $comment
      ->getChangedTime();
    $variables['created'] = $date_formatter
      ->format($comment
      ->getCreatedTime());

    // Avoid calling DateFormatterInterface::format() twice on the same timestamp.
    if ($comment
      ->getChangedTime() == $comment
      ->getCreatedTime()) {
      $variables['changed'] = $variables['created'];
    }
    else {
      $variables['changed'] = $date_formatter
        ->format($comment
        ->getChangedTime());
    }
    if (theme_get_setting('features.comment_user_picture')) {

      // To change user picture settings (for instance, image style), edit the
      // 'compact' view mode on the User entity.
      $variables['user_picture'] = \Drupal::entityTypeManager()
        ->getViewBuilder('user')
        ->view($account, 'compact');
    }
    else {
      $variables['user_picture'] = [];
    }
    $variables['submitted'] = t('Submitted by @username on @datetime', [
      '@username' => $variables['author'],
      '@datetime' => $variables['created'],
    ]);
  }
  if (isset($comment->in_preview)) {
    $variables['permalink'] = Link::fromTextAndUrl(t('Permalink'), Url::fromRoute('<front>'))
      ->toString();
  }
  else {
    $variables['permalink'] = Link::fromTextAndUrl(t('Permalink'), $comment
      ->permalink())
      ->toString();
  }
  if (($comment_parent = $comment
    ->getParentComment()) && (!$skip_custom_preprocessing || !$comment
    ->getFieldDefinition('pid')
    ->isDisplayConfigurable('view'))) {

    // Fetch and store the parent comment information for use in templates.
    $account_parent = $comment_parent
      ->getOwner();
    $variables['parent_comment'] = $comment_parent;
    $username = [
      '#theme' => 'username',
      '#account' => $account_parent,
    ];
    $variables['parent_author'] = \Drupal::service('renderer')
      ->render($username);
    $variables['parent_created'] = $date_formatter
      ->format($comment_parent
      ->getCreatedTime());

    // Avoid calling DateFormatterInterface::format() twice on same timestamp.
    if ($comment_parent
      ->getChangedTime() == $comment_parent
      ->getCreatedTime()) {
      $variables['parent_changed'] = $variables['parent_created'];
    }
    else {
      $variables['parent_changed'] = $date_formatter
        ->format($comment_parent
        ->getChangedTime());
    }
    $permalink_uri_parent = $comment_parent
      ->permalink();
    $attributes = $permalink_uri_parent
      ->getOption('attributes') ?: [];
    $attributes += [
      'class' => [
        'permalink',
      ],
      'rel' => 'bookmark',
    ];
    $permalink_uri_parent
      ->setOption('attributes', $attributes);
    $variables['parent_title'] = Link::fromTextAndUrl($comment_parent
      ->getSubject(), $permalink_uri_parent)
      ->toString();
    $variables['parent_permalink'] = Link::fromTextAndUrl(t('Parent permalink'), $permalink_uri_parent)
      ->toString();
    $variables['parent'] = t('In reply to @parent_title by @parent_username', [
      '@parent_username' => $variables['parent_author'],
      '@parent_title' => $variables['parent_title'],
    ]);
  }
  else {
    $variables['parent_comment'] = '';
    $variables['parent_author'] = '';
    $variables['parent_created'] = '';
    $variables['parent_changed'] = '';
    $variables['parent_title'] = '';
    $variables['parent_permalink'] = '';
    $variables['parent'] = '';
  }
  if (!$skip_custom_preprocessing || !$comment
    ->getFieldDefinition('subject')
    ->isDisplayConfigurable('view')) {
    if (isset($comment->in_preview)) {
      $variables['title'] = Link::fromTextAndUrl($comment
        ->getSubject(), Url::fromRoute('<front>'))
        ->toString();
    }
    else {
      $uri = $comment
        ->permalink();
      $attributes = $uri
        ->getOption('attributes') ?: [];
      $attributes += [
        'class' => [
          'permalink',
        ],
        'rel' => 'bookmark',
      ];
      $uri
        ->setOption('attributes', $attributes);
      $variables['title'] = Link::fromTextAndUrl($comment
        ->getSubject(), $uri)
        ->toString();
    }
  }

  // Helpful $content variable for templates.
  foreach (Element::children($variables['elements']) as $key) {
    $variables['content'][$key] = $variables['elements'][$key];
  }

  // Set status to a string representation of comment->status.
  if (isset($comment->in_preview)) {
    $variables['status'] = 'preview';
  }
  else {
    $variables['status'] = $comment
      ->isPublished() ? 'published' : 'unpublished';
  }

  // Add comment author user ID. Necessary for the comment-by-viewer library.
  $variables['attributes']['data-comment-user-id'] = $comment
    ->getOwnerId();

  // Add anchor for each comment.
  $variables['attributes']['id'] = 'comment-' . $comment
    ->id();
}

/**
 * Prepares variables for comment field templates.
 *
 * Default template: field--comment.html.twig.
 *
 * @param array $variables
 *   An associative array containing:
 *   - element: An associative array containing render arrays for the list of
 *     comments, and the comment form. Array keys: comments, comment_form.
 *
 * @todo Rename to template_preprocess_field__comment() once
 *   https://www.drupal.org/node/939462 is resolved.
 */
function comment_preprocess_field(&$variables) {
  $element = $variables['element'];
  if ($element['#field_type'] == 'comment') {

    // Provide contextual information.
    $variables['comment_display_mode'] = $element[0]['#comment_display_mode'];
    $variables['comment_type'] = $element[0]['#comment_type'];

    // Append additional attributes from the first field item.
    $variables['attributes'] += $variables['items'][0]['attributes']
      ->storage();

    // Create separate variables for the comments and comment form.
    $variables['comments'] = $element[0]['comments'];
    $variables['comment_form'] = $element[0]['comment_form'];
  }
}

/**
 * Implements hook_ranking().
 */
function comment_ranking() {
  return \Drupal::service('comment.statistics')
    ->getRankingInfo();
}

/**
 * Implements hook_ENTITY_TYPE_presave() for entity_view_display entities.
 */
function comment_entity_view_display_presave(EntityViewDisplayInterface $display) {

  // Act only on comment view displays being disabled.
  if ($display
    ->isNew() || $display
    ->getTargetEntityTypeId() !== 'comment' || $display
    ->status()) {
    return;
  }
  $storage = \Drupal::entityTypeManager()
    ->getStorage('entity_view_display');
  if (!$storage
    ->loadUnchanged($display
    ->getOriginalId())
    ->status()) {
    return;
  }

  // Disable the comment field formatter when the used view display is disabled.
  foreach ($storage
    ->loadMultiple() as $view_display) {
    $changed = FALSE;

    /** @var \Drupal\Core\Entity\Display\EntityViewDisplayInterface $view_display */
    foreach ($view_display
      ->getComponents() as $field => $component) {
      if (isset($component['type']) && $component['type'] === 'comment_default') {
        if ($component['settings']['view_mode'] === $display
          ->getMode()) {
          $view_display
            ->removeComponent($field);

          /** @var \Drupal\Core\Entity\EntityViewModeInterface $mode */
          $mode = EntityViewMode::load($display
            ->getTargetEntityTypeId() . '.' . $display
            ->getMode());
          $arguments = [
            '@id' => $view_display
              ->id(),
            '@name' => $field,
            '@display' => $mode
              ->label(),
            '@mode' => $display
              ->getMode(),
          ];
          \Drupal::logger('system')
            ->warning("View display '@id': Comment field formatter '@name' was disabled because it is using the comment view display '@display' (@mode) that was just disabled.", $arguments);
          $changed = TRUE;
        }
      }
    }
    if ($changed) {
      $view_display
        ->save();
    }
  }
}

/**
 * Implements hook_field_type_category_info_alter().
 */
function comment_field_type_category_info_alter(&$definitions) {

  // The `comment` field type belongs in the `general` category, so the
  // libraries need to be attached using an alter hook.
  $definitions[FieldTypeCategoryManagerInterface::FALLBACK_CATEGORY]['libraries'][] = 'comment/drupal.comment-icon';
}

Functions

Namesort descending Description
comment_cron Implements hook_cron().
comment_entity_extra_field_info Implements hook_entity_extra_field_info().
comment_entity_insert Implements hook_entity_insert().
comment_entity_predelete Implements hook_entity_predelete().
comment_entity_storage_load Implements hook_entity_storage_load().
comment_entity_view Implements hook_entity_view().
comment_entity_view_display_presave Implements hook_ENTITY_TYPE_presave() for entity_view_display entities.
comment_field_config_create Implements hook_ENTITY_TYPE_create() for 'field_config'.
comment_field_config_delete Implements hook_ENTITY_TYPE_delete() for 'field_config'.
comment_field_config_update Implements hook_ENTITY_TYPE_update() for 'field_config'.
comment_field_info_entity_type_ui_definitions_alter Implements hook_field_info_entity_type_ui_definitions_alter().
comment_field_storage_config_insert Implements hook_ENTITY_TYPE_insert() for 'field_storage_config'.
comment_field_type_category_info_alter Implements hook_field_type_category_info_alter().
comment_form_field_ui_display_overview_form_alter Implements hook_form_FORM_ID_alter().
comment_form_field_ui_field_storage_add_form_alter Implements hook_form_FORM_ID_alter() for field_ui_field_storage_add_form.
comment_form_field_ui_form_display_overview_form_alter Implements hook_form_FORM_ID_alter().
comment_help Implements hook_help().
comment_node_links_alter Implements hook_node_links_alter().
comment_node_search_result Implements hook_node_search_result().
comment_node_update_index Implements hook_node_update_index().
comment_node_view_alter Implements hook_ENTITY_TYPE_view_alter() for node entities.
comment_preprocess_block Implements hook_preprocess_HOOK() for block templates.
comment_preprocess_field Prepares variables for comment field templates.
comment_preview Generates a comment preview.
comment_ranking Implements hook_ranking().
comment_theme Implements hook_theme().
comment_uri Entity URI callback.
comment_user_cancel Implements hook_user_cancel().
comment_user_predelete Implements hook_ENTITY_TYPE_predelete() for user entities.
template_preprocess_comment Prepares variables for comment templates.
_comment_entity_uses_integer_id Determines if an entity type is using an integer-based ID definition.

Constants

Namesort descending Description
COMMENT_NEW_LIMIT The time cutoff for comments marked as read for entity types other node.